Destruction device for injection needles

ABSTRACT

A device for the destruction of an injection needle has a sleeve (6; 14) in which the needle (3) mounted on a syringe may be inserted. The sleeve includes projections (9; 16) located beneath one another and projecting from opposite sides towards the path of movement of the needle within the sleeve. The projections are forced, by means of an actuator (5; 16) which is movably disposed in the sleeve and, as a result of engagement with the needle holder (4) is entrained in the movement of the needle, to move towards and into the path of movement of the needle so that the needle is bent or broken between these projections and is, in such a manner, rendered unusable.

At the present time, not only large and complicated destructioninstallations which are under municipal supervision and take care of thehazardous waste from local hospitals but also simpler devices used in,for example, medical reception centres and by dentists are utilized forthe destruction of different types of injection syringes in order thatthese shall not, after use, be capable of injury or infection and shallnot be re-usable. A further large number of injection syringes are usedin the home in the occurrence of different illnesses, for example bysufferers from diabetes and asthma. The patients are recommended orinstructed, for the destruction of such injection syringes, to bend orpossibly break the needle or cannula, for example with the protectivecap of the needle, and to break or burn the syringe cylinder beforethese are deposited in the dustbin.

However, in particular this latter method of needle destructionrecommended for patients in the home is highly unsatisfactory. Apartfrom the fact that the recommended or prescribed method is oftendisregarded completely as a result of forgetfulness or carelessness,this method requires the use of such force for breaking or bending theneedle as many patients are unable to produce, with the result that theneedle finds its way into the refuse bag in more or less original shapeand can poke through the bag with the resultant risk of injury andinfection. Furthermore, a needle which is not bent sufficiently may,after retrieval from the refuse bag, quite easily be straightened againby unlawful or unauthorized users who, alternatively, may, for purposesof re-use, break and sharpen the needle at the point of fracture, sincerelatively short needle lengths may also then be used.

The major aspect of the present invention is to obviate thesedisadvantages and thus to realize a needle destruction device whicheliminates or, at least, considerably reduces the risks of injury orinfection from the destroyed needle, as well as the risks of its reuse.

This aspect is achieved, according to the invention, by means of adevice having the characteristics which are apparent from one or more ofthe accompanying claims.

The invention will be described in greater detail below with referenceto the accompanying drawing, on which

FIG. 1 shows one embodiment in the needle-protecting state,

FIG. 2 shows the same embodiment in the needle-destruction state and

FIG. 3 shows a further embodiment in the needle-destruction state.

FIG. 1 shows a conventional syringe assembly S which comprises aninjection piston 1, an injection cylinder 2 and a needle or cannula 3,together with a needle destruction device D, according to the invention,disposed on the needle. The conventional conical needle holder 4 isaccommodated with sliding fit in a corresponding conical upper, innerportion of a cylindrical inner sleeve 5 which is provided with a bottomand concentrically surrounds the needle. The inner sleeve is, in itsturn, concentric with and connected to a cylindrical outer sleeve 6 alsoprovided with a bottom. This connection is realized by means of a numberof studs 7 on the outer side of the upper portion of the inner sleeve 5and corresponding recesses 8, in which the studs 7 engage, on the insideof the upper, thickened portion of the outer sleeve 6. A number of steelblades 9 are fixedly retained below the upper portion of the outersleeve 6 in the inner wall of the outer sleeve, the blades beingdisposed along two diametrically opposed vertical lines so as to form azig-zag pattern. The blades 9 point obliquely towards the longitudinalaxis of the sleeves 5 and 6 containing the needle 3, in a directiontowards the needle holder 4, and extend through holes 10 in the innersleeve 5 so that their tips terminate a distance from the needle 3. Thelength of the blades is greater than the perpendicular distance betweenthe needle 3 and the anchorage points of the blades in the outer sleeve6.

The sleeve 6 is made of yieldable material and may consist of a suitablethermoplastic, such that the blades 9 may be considered as beingpivotally retained in the inner wall of the sleeve 6. The retention ofthe blades 9 in the inner wall of the sleeve 6 may be realized by, forexample, injection moulding of the sleeve 6 around blades 9 disposed inthe sleeve mould.

For unification of the sleeves 5 and 6, for example, the outer sleeve 6with the blades 9 may be produced without a bottom and the inner sleeve5 may be forced into the outer sleeve 6 through its bottom opening andbe twisted until the blades 9 snap into the holes 10, whereafter abottom is fixed, for example, by welding, to the outer sleeve 6.

The syringe assembly S and destruction device D may, in the combinedstate shown in FIG. 1, be sealed in a conventional manner, in a sterilepackage.

The function of the destruction device is as follows. When the syringeassembly S has been removed from its conventional, sterile transportpackage and withdrawn from the combination of the interconnected sleeves5 and 6 which, prior to this withdrawal, also serve as a needleprotector, the syringe assembly is ready for charging with the injectionfluid and for performing the injection operation. When the injectionoperation has been carried out, the syringe assembly is reinserted intothe combination of the sleeves 5 and 6 and, for destruction of theneedle 3, the syringe assembly, together with the sleeves 5 and 6, isstruck or pressed with the tip of the sleeve 6 against some object, forexample, a table top. As a result, while the needle holder 4 is inengagement with the corresponding conical portion of the inner sleeve 5,the studs 7 are, because of the yieldability of the material of thesleeve 6, forced out of the recesses 8 and the inner sleeve 5 movestowards the bottom of the outer sleeve 6. Durng this movement, theblades 9 are forced to pivot downwardly by the defining walls of theholes 10 and are gradually moved into engagement with the needle 3 inorder finally to bend the needle, or, if the needle is of brittlematerial, break it between them by the leverage effect on the needle.Thus, one blade tip serves as a fulcrum while the bending operation iseffected by means of the adjacent blades.

It is possible, in order to realize as short a straight needle tipportion as possible, to provide the inner sleeve, as is shown on thedrawing, with an inwardly projecting abutment 11 at its lowermostportion, this abutment serving as a stop when the bending operation iseffected on the needle by means of the lowermost blade.

Preferably, provision should be made to allow for so much freedom ofmovement for the inner sleeve 5 towards the bottom of the outer sleeve 6that the blades 9, during the impression of the inner sleeve 5 in theouter sleeve 6, may pivot somewhat past the position where they make anangle of 90° with the needle 3 such that retraction of the syringeassembly and thereby of the needle from the sleeve 5 is rendered moredifficult. Moreover, the inner diameter of the inner sleeve 5 shouldpreferably be such that the needle 3 is, during its movement, clampedbeween the blade tips and the inner wall of the sleeve 5 so that theneedle is flattened at the points of contact with the blade tips.

A second series of recesses 12 is provided beneath the recesses 8 forindicating a sufficient impression of the inner sleeve 5 in the outersleeve 6 and, thus, for indicating the completion of the contemplatedbending of the needle 3. The studs 7 snap into these second recesses 12when the above-mentioned sufficient impression has been realized.

In order to prevent impression of the inner sleeve 5 and needle 3 such adistance into the outer sleeve 6 that the blades 9 relax their grip onthe bent needle 3, the inner sleeve 5 may "bottom" in the outer sleeve 6at a blade position where the contemplated bending has been achieved.

After bending or breaking of the needle 3, the syringe cylinder 2 withthe piston 1 may, in a conventional manner, be broken away from theneedle holder 4 at an indication of fracture 13 provided for thispurpose. Otherwise, the syringe cylinder may be withdrawn from theholder 4, depending upon whether the syringe is integrally designed withthe needle holder (that is to say if the syringe is of the singleuse,disposable type), or if the cylinder and piston of the syringe areintended for re-use and have a releasable connection with the needleholder 4.

The bent or broken needle 3 is now in safe keeping in the sleeves 5 and6 and cannot cause injury. Attempts to separate the sleeves 5 and 6would meet with great difficulty and would be of no use to unlawful orunauthorized users, since the needle is bent or broken into unusableshort lengths.

FIG. 3 shows an alternative embodiment of the destruction deviceaccording to the invention in the needle-destruction position. Theembodiment D comprises a sleeve 14 whose inner wall has a conicallytapering portion 15. A U-shaped strip 16 of relatively resilientmaterial, such as plastic or metal, is inserted in the sleeve, theouter, bottom surface of the strip being turned to face in the directionof taper of the portion 15. The shanks of the U-shaped strip haveprojections 17 pointing towards each other, an arrangement which may berealized by inward bending of portions of the shanks of the strip 16.When the forward portion of the syringe is inserted in the sleeve (theU-shaped strip being in an upper position in the portion 15 and ready toreceive the needle between its shanks), the U-shaped strip 16 is forcedand entrained by means of the needle holder in the direction of taper ofthe portion 15, as a result of which the shanks of the strip 16 areforced in a direction towards each other in the conical portion 15 sothat the projections 17 grasp and gradually bend or break the needle ofthe syringe between them, as shown on the drawing.

The conically tapering inner portion 15 need not have an axis ofsymmetry, as shown in FIG. 3, but may be formed by a wall of the sleeve14 parallel to the path of movement of the needle, and an opposing wallinclined with respect to the first wall. In such a case, only thoseprojections 17 which are located on the shank of the U-shaped strip 16adjacent the inclined wall will move in the transverse direction of theneedle.

I claim:
 1. Device for the destruction of the injection needle of aninjection syringe, characterized by a sleeve (6; 14) in which theinjection needle (3) may be inserted and which is provided, in itsinterior, with spaced apart elements (9; 17) in the longitudinaldirection of the sleeve and projecting from opposite directions towardsthe intended path of movement of the needle in the sleeve, and members(5; 16) movable with respect to the sleeve in the longitudinal directionthereof and disposed, during their movement, to influence at least oneof said elements in such a manner that this moves towards and into thepath of movement of the needle.
 2. Device according to claim 1,characterized in that said influencing members (5; 16) are provided withmeans for engagement with the needle holder of the injection syringe. 3.Device according to claim 1 or 2, characterized in that the elements (9)or some of them are, at their one end, pivotally anchored in the innerwall of the sleeve (6) and that the influencing members (5) are disposedto pivot the elements (9) beyond a position where they make a rightangle with the longitudinal axis of the path of movement of the needle,for the purposes of hindering withdrawal of the bent needle from thesleeve (6).
 4. Device according to claim 1, characterized in that saidinfluencing member consists of a second sleeve (5) disposed within thefirst sleeve (6), and through whose side wall the elements (9) projecttowards the path of movement of the needle.
 5. Device according to claim4, characterized in that the second sleeve (5) displays one position inwhich it is in engagement with the first sleeve (6) which engagement isreleasable by the exercising of force on the second sleeve (5) in theinsertion direction of needle (3).
 6. Device according to claim 5,characterized in that studs (7) are disposed, for said engagement, onthe outer side of the second sleeve (5), and first recesses (8) in theinner side of the first sleeve, which first sleeve consists of ayieldable material.
 7. Device according to claim 6, characterized inthat second recesses (12) are provided in the inner side of the firstsleeve (6) in the insertion direction of the needle ahead of the firstrecesses (8), which second recesses are arranged for engagement with thestuds (7) for indicating the contemplated needle-bending or breaking andfor interlocking the sleeves (5, 6).
 8. Device according to any one ofclaims 1-3, characterized in that the sleeve (14) has an inner,conically tapering cavity (15) and that the influencing member (16)consists of a U-shaped resilient strip (16) which may be inserted intothe cavity and support blades on its shanks, between which is definedthe path of movement of the needle.